Patent · US Expired

Calibration of a scanning electron microscope

US6384408B1 · kind B1 · utility

22Cited by
4References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 11, 1999
Grant dateMay 7, 2002
Priority date
Expiry dateAug 11, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2237/30433
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A scanning electron microscope (SEM) is calibrated for the effects of local charging on a measured critical dimension (CD) of a wafer by first calibrating the microscope with respect to a calibration wafer with a known CD. Local charging on a wafer may be measured as a local landing energy (LLE) so that a scale factor based on a ratio of LLEs for the measurement wafer and a calibration wafer is used to correct a measured CD for the measurement wafer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.